<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title></title>
    <script src="../js/vue.js"></script>
</head>
<body>
    <div id="app">
        <counter :num="3"></counter>
    </div>
<br>
<script>
     Vue.component('counter',{
     props:['num'],
     template:'<button @click="num++">点击{{num}}次</button>'
    })
    let vm=new Vue({
        el:'#app'
    })
 </script>
 </body>
</html>